Starter for 10
It depends what the specific performance of the aircraft is and where the "corner point" is on the flight envelope.
I would have thought that ideally you would want to fly to the corner point which is where you get the biggest rate of change of heading for a given g. Slower then the corner point you are limited on AOA and head towards the stall so have to back off the turn rate, faster than the corner point you are structurally limited (max g) and so your turning circle get bigger and bigger as speed increases.
There are huge numbers of factors though such as excess performance at a given flight condition (which will define how quickly you can accelerate the aircraft after a turn). If your acceleration is poor, you might want to keep more speed on and take the hit on the turn rate.